to find zero on the can:
from the bottom of the can, go from the center of the motor mounting screw holes up along side of the can and it will align with a divit close to the top of the can. This divit serves two purposes, first it retains the locking ring of the endbell and second is a second mark for zero.
Timing marks already on endball:
on the side of the endbell, there is a small lip that is visible when the endbell in mounted to the can, and it has 3 marks molded on it near the endbell screws that are used to secure the locking ring. One is a sharp point and the other two are just grooves. The sharp point marks zero and each groove marks 12 degrees.
To set the timing at roughly 12-15 degrees:
Once you have the endbell on the can, oriented correctly for proper rotation, align the endbell mounting screw with the center of the divit on the side of the can. Then you will rotate the endbell counter clockwise until the first mark is just past the center of the divit(roughly 1/32 past the center). This will give you the 15 degrees of timing.